ubuntu phone package support

Hi
I have installed macchanger on my ubuntuphone, but every operation I try (for example "sudo macchanger -m 11:22:33:44:55:66 wlan0"), I get this answer:

[ERROR] Could not change MAC: interface up or insufficient permissions: Operation not supported

I don't think it's a permissions error, because I've made the file system writable, I am in developer mode, I am using sudo and the root user.
The interfaces aren't up.
I think that this operation is blocked by the phone's developers (tryin' to change the MAC address via ifconfig, the answer is: "SIOCSIFHWADDR: Operation not supported").
So after all this I have two questions:
1) Am I making typing errors, or I am right when I say that MAC spoofing is blocked on the ubuntuphone?
2) Are you thinking to make a macchanger's version that supports ubuntuphone, or it is unnecessary? In this case I'll contact the phone developers and will try to convince them to allow this operation.

Thanks
pgcor